ABSTRACT The Biostatistics Core provides expertise in statistical science to ensure scientific rigor in study design, statistical analysis, and interpretation of cancer research studies. The Biostatistics Core is grouped in the Cross Disciplinary Research Core Cluster which, in addition to the Biostatistics Core, includes the Pharmacology, Genomics, and Biobanking and Correlative Sciences Cores. Members of the Core have expertise in a wide range of scientific disciplines including design and analysis of clinical trials, observational studies, in vitro and in vivo studies, biomarker discovery and validation projects, bioinformatics projects in collaboration with the Genomics Core and metabolomics studies in collaboration with the Pharmacology Core. They collaborate with cancer center investigators in the planning phase of studies to ensure that their hypotheses are testable and that the data will be adequate to address the study questions. They provide expertise on data collection and management and devise analysis plans consistent with the study objectives. At the completion of the study they evaluate the data for conformity with the assumptions of the statistical tests, provide estimates of the endpoints with confidence intervals, develop appropriate statistical models, assess the adequacy of the models and prepare written reports to the investigator. The Biostatistics Core has an important role in cancer research at KCI. During the current grant period (12/1/2010 -- 11/30/2014), the Core's collaborative activities resulted in 121 clinical protocols and 263 new cancer research proposals submitted for peer reviewed, external funding. Of these, 178 were submitted to the NCI, 36 to the DOD, and 4 to the Susan G. Komen Foundation. In addition, Biostatistics Core members were co-authors on 87 publications in peer reviewed journals. Core biostatisticians collaborate with investigators from each of the KCI research programs and work with staff from other KCI cores. The Core maintains a variety of statistical applications including general-purpose statistical software, R, SAS and Stata/MP, as well as software for statistical power calculations including PASS and nQuery Advisor. The Core shares an Ingenuity Pathway Analysis (IPA) license with the Genomics Core. Application software resides on a high-performance, multi-processor Dell 820 server. Access to the server is restricted to members of the Biostatistics Core and authorized guests. For intensive computing projects, members of the Core use the WSU high-performance grid, four servers of which have been contributed to KCI, running under Linux, for the use of Core members. These computers are accessible to other authorized KCI members whose research requires high performance computing.